I'm posting this as a new thread with search terms in the title in case it's useful to others; there are many threads trying to figure out audio formats and some frustrated people. I was one of those people until I spent some time testing. The results here apply to my 2020 E63S with high-end Burmester option, but are likely to apply to other W213 cars, especially recent ones.

The car will not read FLAC or MP4 tags. The symptom is that most of the files on your USB drive or SD card will show as "Unknown". You can still browse music by folder, and the files will play in the correct order, if they use the common convention of naming each track file with a 2-digit (or more) number, e.g. "01 - Breathe", "02 - On the run", etc, or even, for a multi-disc album, "1-01 track 1", "1-02 track 2", etc. That way track 10 will play after track 09, disc 2 will play after disc 1, and you won't have the problem of playing the tracks in alphabetical order of track name. But browsing by folder isn't always convenient unless you organize your folders in the way you want to browse them.

If you ripped CDs or bought online music, if it's in FLAC, ALAC or AAC format, your files are likely using FLAC or MP4 tags and the car doesn't see them. If you used EAC to rip your CDs and used the default tagging, you may have ID3 (actually ID3v2) tags in your FLAC files by accident. That causes problems with some FLAC players, but may actually help with COMAND.

Files using ID3 tags, generally ID3v2.3 or ID3v2,4 these days, are recognized correctly by the car and everything works: album art, search by Artist, Album, Title, play order, etc. You may find it cleaner to use the Album Artist data in the Artist tags -- it's easy to copy them over in, say, MP3tag or, even better, Jaikoz. That way, when you search by Artist, you won't get all the guest artists on some albums, unless that's what you want.

Unfortunately, you're likely stuck with 320kbps MP3 as the best format you can use if you want the car to recognize your files and their metadata. It's generally hard to tell the difference between 320kbps MP3 and higher-resolution lossless formats, especially in a moving car, although the Burmester high-end system is unusually resolving. But it bothers some people, me included. The other option that I found to work was to use an MTP-compatible portable player plugged into a USB port. I used an Astell&Kern AK240 set to MTP mode. The car indexed all the FLAC files correctly and everything works fine.

I didn't try, but expect than an iPod would also work, and 256GB iPods are readily available. You'd have to convert any FLACs to ALACs, but there's plenty of free software that does that; I use MediaHuman Audio Converter, because it uses all 64 cores on my PC and takes only a few minutes to convert thousands of files.

I haven't addressed album art here and it's possible that Mercedes imposes limits on size. Given the resolution of the COMAND screen, there's no point in having high-resolution art. It's easy to downsize all the art in your files using dBPowerAmp's batch converter. I just set them all to 400x400 pixels.

I suggest that you create a separate folder on your PC/Mac to house the music files that you want to use in your car. That way you can do things to the files to make them specifically more car-friendly, without affecting your main music collection.

I hope that is is helpful! I've been through this process with other cars and they're all different, even within brands. I guess it proves that the beauty of standards is there are so many of them :-).

 

Thank you for this. Am using FLAC files on a usb stick and it seems to be working okay for me. Files identified properly and indexed by folders, artist, title, genre

 

Great contribution FlyingBear thanks for the effort, have you experimented with portable DAC player?

 

That's very interesting. Did you, by any chance, rip CDs to FLAC using EAC? I ask because EAC will, by default, use the "wrong" metadata type in FLAC files (ID3) which messes up some FLAC players but may actually help with the MB system, which seems to read ID3 metadata but not FLAC or MP4.

If you didn't use EAC, then there's a further mystery, which may, I guess, be related to the specifics of the encoder and how it handles metadata. Or MB's system may be confused by some FLAC tags, e.g. if there are too many of them in a given file. EDIT: I tried FLACs with almost no metadata, just the basics, same issue of the car not recognizing most of the files.

I did, by the way, try a USB stick as well as an SD card, with identical results: my FLAC files >90% not identified.

 

Yes. The Astell & Kern AK240 player I'm using is a few years old, but is still quite high-end with very good built-in DACs. However, when connected to the MB over USB it's just sending digital data and the DACs aren't used; the DAC conversion happens in the bowels of the Burmester system. If the MB had an analog input, I could use the (likely better than Burmeter's) DAC in the AK240 and use its analog balanced or unbalanced output. But it would have to be controlled directly on the AK240, and the MB doesn't AFAIK have an analog input. The main downside of using the AK240 over USB as an MTP player is that it takes 15-20 minutes on every startup to reindex 11,500 tracks. Once that's done the browsing by Artist, Album, Genre, Track, Composer is perfect.

The quickest, highest-quality solution I've found is to put FLACs onto a USB stick and browse by folder. The AK240 allows for full searching and browsing, but the slow startup is annoying. Of course, I could just live with 1,000 tracks on the AK240 and it would start up much faster. In my Taycan, a 256GB USB stick of FLACs was scanned once, and is instantly available for full browsing within seconds of the car powering up. To be sure, it was a pain to ensure that all the album art was small enough -- Porsche doesn't see art larger than 800x800 -- and there were quirks in how picky it was about metadata too.

I'll keep noodling on this in search of the mysterious non-recognition of FLACs on USB or SD, while others don't have that problem. It's made harder by the fact that various models and years or W213 likely have different software and, maybe, even quite different hardware.